延长药包不同位置起爆时的应力场

利用红宝石脉冲激光器建立了三维动态散光光弹性爆破模型实验系统,首次对条形药包在一端起爆、两端同时起爆、药柱中点起爆等条件下的爆破模型进行了研究,得到了在同一剖面的4个时刻的动态应力条纹图;对3种爆破模型的动应力场进行了对比分析,并就其爆破效果提出了相应的结论.     

不同保存方式下金龟甲虫DNA提取方法及28S rDNA序列分析

通过电泳检测和PCR扩增28SrDNA核基因序列的结果,比较了无水乙醇、75%乙醇、针插干制3种金龟甲虫标本的保存方式和SDS-蛋白酶K法、CTAB法、饱和NaCl法3种提取DNA方法.结果显示,SDS-蛋白酶K法、CTAB法提取3种保存方式的标本时,可成功提取DNA并有效扩增目的基因;饱和NaCl法仅能提取无水乙醇保存标本的DNA并扩增目的基因,而75%乙醇保存标本和干制标本的DNA提取和基因扩增均不理想.     

含热电联合系统的微电网运行优化

为了提高微电网的经济运行水平,提出考虑分时电价并计及制热收益的微电网多目标能量调度模型,该模型以微网发电成本最低与环境效益最优为目标。首先,利用权重系数将多目标经济调度问题化成单目标优化问题。其次,针对遗传算法局部搜索能力差的问题,提出了天牛须搜索算法改善遗传算法的变异操作,利用自身对空间的判断,加强局部搜索能力,在此基础上将Metropolis接受准则加入天牛须搜索算法中,增加变异的概率。最后,以一个微电网为例,将改进的算法与标准遗传算法进行对比,验证了所改进的算法的全局最优解的搜索能力,使得微网获得更佳的综合效益,降低了系统经济运行成本。     

网状及条带式加筋土挡墙加筋应变的测试

通过对网状及条带式加筋土挡墙大型模型试验加筋拉应变的测试分析,发现条带式与网状加筋的拉应变自墙背沿加筋长度逐渐减小;在离墙面相同距离处,条带式加筋的拉应变比筋网中筋肋的拉应变大得多;各层加筋的应力水平均随超载的增大而提高,随着超载的增大,条带式加筋前、中部的拉应力增长幅度很大,其后部拉应力增幅较小;而筋网的总体应力水平均有比较均匀的提高,提高的幅度自前部向后端逐渐减小,这说明网状加筋比条带式加筋更适合于修筑加筋土挡墙。     

A new sesquiterpene lactone glucoside and other constituents from Inula salsoloides with insecticidal activities on striped flea beetle (Phyllotreta striolata Fabricius)

A new sesquiterpene, eupatolide 13-O-β-d-glucopyranoside (eupatolide-II, 1), lactone glucoside, along with 15 known compounds, were isolated from the whole plant of Inula salsoloides (Asteraceae). Dichloromethane extract and compounds 1–11 were used to investigate insecticidal activities against vegetable important pest, striped flea beetle (Phyllotreta striolata Fabricius). None of the samples show any toxicity under concentration of 500 times, while compound 1 and the extract had toxic effect when the concentration increased to 250 times. But the corrected mortality of compound 1 and the extract were only 44.83 and 13.80%, respectively. Compound 11 (inulasalene) showed repellency effect in the no-choice test, and the repellency rate was 70%. Compounds 1 and 3 (inulasalsolide) showed the antifeeding rates of 65.22 and 47.06%, respectively. Compound 10 (11β,13-dihydrogeneupatolide) showed strong attractive effects on the adults, while the difference of injured area between the treatment and control was also not significant.     

半自然驯化条件下黑线姬鼠冬夏两季产热的比较

为探讨小型哺乳动物适应于季节性环境的产热机制,本文测定了户外半自然条件下驯化的黑线姬鼠(Apodemus agrarius)冬、夏两季的体重以及肝和褐色脂肪组织(Brown adipose tissue, BAT)的细胞色素c氧化酶及BATα-磷酸甘油氧化酶活力等指标.结果显示黑线姬鼠冬季体重显著降低,BAT绝对重量、BAT和肝的线粒体蛋白含量及BAT和肝酶的活力冬季均显著高于夏季.冬季BAT细胞色素c氧化酶活力是夏季的9.5倍,肝脏细胞色素c氧化酶活力是夏季的5倍;冬季BAT的α-磷酸甘油氧化酶活力高达夏季的19倍.以上结果表明,在寒冷的冬季为保证存活,黑线姬鼠降低体重以减少绝对能量需求,并极大地增加BAT重量及肝和BAT细胞水平上的产热能力.     

烟草甲虫性信息素(7S)-(-)-4,6-二甲基-7-羟基-3-壬酮的立体选择性合成

手性试剂;烟草甲虫性信息素(7S)-(-)-4;6-二甲基-7-羟基-3-壬酮的立体选择性合成     

A theoretical model for striped patterns in nematic hydrogels

Both nematic elastomers and nematic hydrogels are known to display striped patterns.In contrast to a large body of proposed models for nematic elastomers,few studies exist to interpret striping in nematic hydrogels.In this paper,a theoretical model based on free energyminimization is developed to simulate the drying-induced striping in a layer of nematic hydrogel bonded to a rigid substrate.The liquid crystalline polymers in the nematic hydrogel rotate by certain angles to form the striping in response to a drying environment.Moreover,the striping occurs only for a finite range of humidity,and the boundaries of this range can be tuned.     

基于改进神经网络及地理信息系统空间分析的风暴潮经济损失评估

台风风暴潮是影响我国最严重的海洋灾害之一,台风风暴潮经济损失的预评估对防灾减灾有重要作用。针对目前大量单机器学习模型评估效果不佳的问题,提出基于天牛须搜索算法优化的BP神经网络及GIS空间分析的台风风暴潮经济损失评估模型。该模型在神经网络训练前,先利用天牛须搜索算法对神经网络的初始权值阈值进行优化,以提高网络的寻优精度;在网络输出计算结果后,借助GIS空间分析功能找出待评估台风风暴潮的相似样本,并用相似样本对待评估台风风暴潮进行结果调整;最后基于悲观、乐观估计思想,给出台风风暴潮经济损失预评估区间。计算结果表明,结合GIS空间分析调整能给出更有效的模型评估结果。